In this Article

Are there any interactions with medications?

EphedrineInteraction Rating:
Major Do not take this combination.

Stimulant drugs speed up the nervous system. Caffeine and ephedrine are both stimulant drugs. Taking caffeine along with ephedrine might cause too much stimulation and sometimes serious side effects and heart problems. Do not take caffeine-containing products and ephedrine at the same time.

Adenosine (Adenocard)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Caffeine might block the effects of adenosine (Adenocard). Adenosine (Adenocard) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming caffeine-containing products at least 24 hours before a cardiac stress test.

The body breaks down caffeine to get rid of it. Some antibiotics might decrease how quickly the body breaks down caffeine. Taking these antibiotics along with caffeine can increase the risk of side effects including jitteriness, headache, increased heart rate, and other side effects.

Cimetidine (Tagamet)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Cimetidine (Tagamet) can decrease how quickly your body breaks down caffeine. Taking cimetidine (Tagamet) along with caffeine might increase the chance of caffeine side effects including jitteriness, headache, fast heartbeat, and others.

Clozapine (Clozaril)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down clozapine (Clozaril) to get rid of it. Caffeine seems to decrease how quickly the body breaks down clozapine (Clozaril). Taking caffeine along with clozapine (Clozaril) can increase the effects and side effects of clozapine (Clozaril).

Dipyridamole (Persantine)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Caffeine might block the affects of dipyridamole (Persantine). Dipyridamole (Persantine) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming caffeine-containing products at least 24 hours before a cardiac stress test.

Disulfiram (Antabuse)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Disulfiram (Antabuse) can decrease how quickly the body gets rid of caffeine. Taking caffeine along with disulfiram (Antabuse) might increase the effects and side effects of caffeine including jitteriness, hyperactivity, irritability, and others.

EstrogensInteraction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking caffeine along with estrogens might cause jitteriness, headache, fast heartbeat, and other side effects. If you take estrogens limit your caffeine intake.

Fluvoxamine (Luvox)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Fluvoxamine (Luvox) can decrease how quickly the body breaks down caffeine. Taking caffeine along with fluvoxamine (Luvox) might cause too much caffeine in the body, and increase the effects and side effects of caffeine.

LithiumInteraction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

You body naturally gets rid of lithium. Caffeine can increase how quickly your body gets rid of lithium. If you take products that contain caffeine and you take lithium, stop taking caffeine products slowly. Stopping caffeine too quickly can increase the side effects of lithium.

Medications for asthma (Beta-adrenergic agonists)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Caffeine can stimulate the heart. Some medications for asthma can also stimulate the heart. Taking caffeine with some medications for asthma might cause too much stimulation and cause heart problems.

Medications for depression (MAOIs)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Caffeine can stimulate the body. Some medications used for depression can also stimulate the body. Taking caffeine along with some medications for depression might cause serious side effects including fast heartbeat, high blood pressure, nervousness, and others.

Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.

Pentobarbital (Nembutal)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

The stimulant effects of caffeine can block the sleep-producing effects of pentobarbital.

PhenylpropanolamineInteraction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Caffeine can stimulate the body. Phenylpropanolamine can also stimulate the body. Taking caffeine along with phenylpropanolamine might cause too much stimulation and increase heartbeat, blood pressure, and cause nervousness.

Riluzole (Rilutek)Interaction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down riluzole (Rilutek) to get rid of it. Taking caffeine along with riluzole (Rilutek) might decrease how fast the body breaks down riluzole (Rilutek) and increase the effects and side effects of riluzole (Rilutek).

Stimulant drugsInteraction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Stimulant drugs speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and speed up your heart rate. Caffeine might also speed up the nervous system. Taking caffeine along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.

TheophyllineInteraction Rating:
Moderate Be cautious with this combination.Talk with your health provider.

Caffeine works similarly to theophylline. Caffeine can also decrease how quickly the body gets rid of theophylline. Taking theophylline along with caffeine might increase the effects and side effects of theophylline.

The body breaks down caffeine to get rid of it. Verapamil (Calan, Covera, Isoptin, Verelan) can decrease how quickly the body gets rid of caffeine. Taking caffeine along with verapamil (Calan, Covera, Isoptin, Verelan) can increase the risk of side effects for caffeine including jitteriness, headache, and an increased heartbeat.

AlcoholInteraction Rating:
Minor Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Alcohol can decrease how quickly the body breaks down caffeine. Taking caffeine along with alcohol might cause too much caffeine in the bloodstream and caffeine side effects including jitteriness, headache, and fast heartbeat.

Birth control pills (Contraceptive drugs)Interaction Rating:
Minor Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. Taking caffeine along with birth control pills can cause jitteriness, headache, fast heartbeat, and other side effects.

Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.

Fluconazole (Diflucan)Interaction Rating:
Minor Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Fluconazole (Diflucan) might decrease how quickly the body gets rid of caffeine. Taking caffeine along with fluconazole (Diflucan) might cause caffeine to stay in to body too long and increase the risk of side effects such as nervousness, anxiety, and insomnia.

Medications for diabetes (Antidiabetes drugs)Interaction Rating:
Minor Be cautious with this combination.Talk with your health provider.

Mexiletine (Mexitil)Interaction Rating:
Minor Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Mexiletine (Mexitil) can decrease how quickly the body breaks down caffeine. Taking Mexiletine (Mexitil) along with caffeine might increase the effects and side effects of caffeine.

Terbinafine (Lamisil)Interaction Rating:
Minor Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Terbinafine (Lamisil) can decrease how fast the body gets rid of caffeine. Taking caffeine along with terbinafine (Lamisil) can increase the risk of caffeine side effects including jitteriness, headache, increased heartbeat, and other effects.

Dosing considerations for Caffeine.

The following doses have been studied in scientific research:

BY MOUTH:

For headache or improving mental alertness: 250 mg per day.

For tiredness: 150-600 mg.

For improving athletic performance: 2-10 mg/kg or more has been used. However, doses in excess of 800 mg per day can result in urine levels greater than the 15 mcg/mL allowed by the National Collegiate Athletic Association.

For weight loss: the ephedrine/caffeine combination products are commonly dosed 20 mg/200 mg three times per day.

For headache after epidural anesthesia: 300 mg.

For preventing gallstone disease: intake of 400 mg or more of caffeine per day.

For preventing Parkinson's disease: men drinking 421-2716 mg of total caffeine daily have the lowest risk of developing Parkinson's disease, when compared to other men. However, men who drink as little as 124-208 mg of caffeine daily also have a significantly lower chance of developing Parkinson's disease. In women, moderate caffeine intake per day (1-3 cups of coffee per day) seems to be best.

One cup of brewed coffee provides from 95-200 mg of caffeine. An 8-ounce serving of black tea provides from 40-120 mg of caffeine. An 8-ounce serving of green tea provides 15-60 mg of caffeine. Soft drinks such as cola provide from 20-80 mg of caffeine per 12 ounce serving. Sports or energy drinks typically provide from 48-300 mg of caffeine per serving.

INTRAVENOUS:

Caffeine is given intravenously (by IV) by healthcare providers for breathing problems in infants and for headache after epidural anesthesia.